The term "flipped classroom" is relatively recent, but a related idea, "programmed instruction", has been around for a long time (and was invented by BF Skinner). Quoting Wikipedia:
It typically consists of self-teaching with the aid of a specialized textbook or teaching machine that presents material structured in a logical and empirically developed sequence or sequences. Programmed instruction may be presented by a teacher as well, and it has been argued that the principles of programmed instruction can improve classic lectures and textbooks.Programmed instruction allows students to progress through a unit of study at their own rate, checking their own answers and advancing only after answering correctly. In one simplified form of PI, after each step, they are presented with a question to test their comprehension, then are immediately shown the correct answer or given additional information. However the objective of the instructional programming is to present the material in very small increments.
The Wikipedia article lists several programmed instruction textbooks, many teaching computer programming. Khan Academy, with its lectures and accompanying problems, where answering enough questions moves you to the next topic, could be considered programmed instruction, as could EPGY. Stanford professor Patrick Suppes has been working on EPGY-like systems since the 1960s, as documented at
http://suppes-corpus.stanford.edu/browse.html?c=comped&d=1960 .
The idea of students working largely on their own, getting canned instruction (either printed or video) and getting automated feedback as they work problems, has been around for a long time. I don't know if it is unpopular because
(1) it does not work well for most students -- they need live instruction or feedback
(2) school administrators don't want some students getting much ahead of others
(3) automating instruction threatens teacher employment
I looked at a programmed algebra textbook. The snippets of exposition between problems, typically just a few lines, could frustrate students who want to see the big picture.
